GLOSSARY

RGB Video

The video output (analog or digital) of most computers. Analog RGB video can have 3, 4,

 

or 5 wires - one each for red, green, and blue, and either none, one or two for sync. For

 

three-wire RGB, the green wire usually provides sync. (See TTL Video).

RS-232

A common asynchronous data transmission standard recommended by the Electronics

 

Industries Association (EIA). Also called serial communication.

RS-422

A less common asynchronous data transmission standard in which balanced differential

 

voltage is specified. RS-422 is especially suited to long distances.

S-Video

The output from certain video tape players and video equipment. S-Video separates sync

 

and luminance from color information, typically producing a higher quality display than

 

composite video.

Scan Frequency

The horizontal or vertical frequency at which images are generated.

Scan Line

One horizontal line on the display.

SECAM

A video output format of some video tape and disc players (used primarily in France).

 

SECAM (Sequential Couleur á Mémoire) signals are similar in resolution and frequency

 

to PAL signals. The primary difference between the two standards is in the way color

 

information is encoded.

Slidebar

A slidebar is a graphical display of an adjustable setting. The numerical setting often rep-

 

resents a percentage but can be a specific unit such as degrees Kelvin.

Source

The device, such as a computer or VCR, connected to the projector for display. A source

 

is identified at the projector as

 

,

Input2

,

Input3

, or

Input4

, or as other user-defined num-

 

Input1

 

 

bers. A source may have numerous corresponding channels defined and recognized by the

 

projector. See Input.

Source Setup

See Channel.

Spot Size

The diameter of the smallest dot that can be generated by a CRT projector. This projector

 

has a fixed spot (pixel) size.

Sync

This term refers to the part of the video signal that is used to stabilize the picture. Sync

 

can occur in three forms:

 

1) "Composite sync": the horizontal and vertical components are together on

 

one cable.

 

2) "Sync-on-green": the sync is part of the green video.

 

3) "Separate sync" or "H.SYNC and V.SYNC": the horizontal and vertical

 

components of the sync are on two separate cables.

Sync Width

The duration of each sync pulse generated by a computer. The sync width is part of the

 

blanking time.

TTL Video

A type of RGB video with digital characteristics.

Terminated

A wire connecting a single video source to a display device, such as a projector, must be

 

terminated by a resistance (usually 75Ω for video).

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Runco VX-6C RGB Video, RS-232, RS-422, Scan Frequency, Scan Line, Slidebar, Source Setup, Spot Size, Sync Width